Spray dampening system with individual metering pumps for offset press

ABSTRACT

Individual, low volume metering pumps are provided for supplying moisture to each nozzle in a bank of adjacent nozzles directing moisture toward the inking train. The metering pumps are driven through commonly mounted eccentric cam rollers respectively engaging adjustable rocker arms for accurately varying the moisture output of each nozzle while variation of a master drive controls overall bank output. Selectively operable pistons are associated with individual output check valves for system priming or bubble clearance.

Ilnite Smith, ,Ir.

[22] Filed:

[54] SPRAY DAMPENING SYSTEM WITH INDIVIDUAL METERING PUMPS FOR OFFSETPRESS [72] Inventor: Roy R. Smith, Jr., 9714 Cherokee Lane,

Leawood, Kans. 66952 [52] 11.8. C1 ..'.101/ll47 [51] Int. Cl ..B41l25/06[58] FieldofSearch ..l01/147,366,202;417/435, 417/471 [56] ReferencesCited UNITED STATES PATENTS 410,188 9/1889 Partington ..10l/147 UX1,589,148 6/1926 Halliwell.... ....101/207 X 2,231,666 2/1941 Golber........101/147 2,389,730 11/1945 ller ....l01/l47 3,056,384 10/1962 Bealeet a1. ....101/202 2,180,818 ll/1939 Fields ..417/471 2,448,226 8/1948Marsden.. 101/147 2,469,796 5/1949 Stobb 101/366 UX 2,603,159 7/1952Johnson... ..4l7/435 2,687,696 3/1954 Theis .417/435 3,065,693 11/1962Neal 101/366 3,134,326 5/1964 Davis ..101/366 3,238,967 3/1966 Smith......4l7/471 X 3,411,718 ll/l968 Wagner ..101/147X Primary ExaminerRobertE. Pulfrey Assistant Examiner--R. E. Suter Attorney-Fishburn, Gold andLitman [57] ABSTRACT Individual, low volume metering pumps are providedfor supplying moisture to each nozzle in a bank of adjacent nozzlesdirecting moisture toward the inking train. The metering pumps aredriven through commonly mounted eccentric cam rollers respectivelyengaging adjustable rocker arms for accurately varying the moistureoutput of each nozzle while variation of a master drive controls overallbank output. Selectively operable pistons are associated with individualoutput check valves for system priming or bubble clearance.

9 Claims, 8 Drawing Figures PATENTEBMARZB I972 3,651,756

' SHEET 1 OF 5 RNE PATENTEDHAR 2 8 I972 SHEET 2 BF 5 INTR. N 0y R.SmiHnJr.

ATTORNEYS PATENTEBMARZB I972 3,651,756

INVENTOR.

R y R. Smiih Jr. BY

ATTOR N EYS PATENTEUMAR28 1972 SHEET 4 0F 5 INVENTOR.

y R. smaw, JV.

w. WW 0 R N EYS mm B w ll m l w w MW PATENTEBHAR28 IHYE SHEET 5 BF 5INVENTOR may 5mi1'h,Jr-. Y

gydm ATTORNEYS Wat mm mm flaw SPRAY DAMPENING SYSTEM WITH INDIVIDUALMETERING PUMPS FOR OFFSET PRESS This invention relates to improveddampening apparatus for lithographic offset printing presses and moreparticularly to such apparatus which permits fine control for optimumdampening under highly varied conditions of press speed and inkrequirements.

It is known that the practice of offset lithography printing requiressufficient but not excessive dampening of the printing member to allowink transfer where desired and yet prevent ink from adhering to thoseportions of the member which are free of printing areas. Devices forsupplying moisture to printing presses for this purpose are numerous andvary greatly in complexity and operation. Heretofore, however, the useof such devices has presented certain drawbacks which tend to adverselyaffect the speed, cost or quality of production.

Among these drawbacks are: lack of precise control so that an improperquantity of moisture is supplied for the particular press speed;insufficient or excess moisture in certain positions along the printingplate where printing density varies from neighboring areas;contamination of the moisture supply due to paper lint or other foreignmaterial entering open moisture reservoirs or exposed dampening rolls;contamination of the moisture supply due to improper ink movement; andimproper composition of dampening mixture due to the evaporation ofvolatile components from exposed supply sources.

The principal objects of the present invention are: to provide dampeningapparatus for offset printing presses which overcomes the above-noteddisadvantages; to provide such apparatus which is relatively inexpensiveto manufacture and easily adapted to the printing press; and to providesuch apparatus which is highly reliable and requires a minimum amount ofattention for operation or maintenance.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawings wherein are set forth by way of illustration and examplecertain embodiments of this invention.

FIG. 1 (A and B) is a fragmentary side elevation illustrating dampeningapparatus embodying this invention including a pump member and a spraymember mounted on a rotary web press with portions broken away to showinterior construction.

FIG. 2 is a fragmentary plan view illustrating the pump member of FIG.1A with portions broken away further showing interior construction.

FIG. 3 is a fragmentary plan view illustrating the spray member of FIG.1B with portions broken away showing interior construction.

FIG. 4 is a front elevational view of the spray member of FIG. 3.

FIG. 5 is a rear elevational view of the spray member of FIG. 3 with theback plate removed.

FIG. 6 is an end elevation of the spray member of FIG. 3.

FIG. 7 is a cross-sectional view through the spray member taken on theline 7-7, FIG. 3, particularly showing passageway construction forfeeding air and liquid to the respective nozzles.

The reference numeral 1 generally indicates dampening apparatusembodying this invention. The apparatus 1 is illustrated in conjunctionwith rotary web printing press 2 (FIG. 1B) of a conventional type havingan ink transfer train 3 including an ink fountain 4, hard metal rollers5-9 and relatively soft (rubber) rollers 10-17. Through the ink transfertrain 3, ink 18 in the fountain 4 is evenly distributed and transferredto the lithographic printing plate 19 on a plate roller 20. The ink 18adheres to the plate 19 only at predetermined locations, and the imageformed is transferred to a blanket cylinder 21. From the cylinder 21,the image is deposited upon the moving paper web 22 which is maintainedin contact with the cylinder 21 by means of an impression cylinder 23.The press cylinders above described are driven directly or indirectlythrough a typical drive shaft 24 which synchronizes the printingoperation with other parts of the printing press in a known manner.

Referring to this invention, the apparatus 1 includes a spray member 25(FIG. 18) mounted on the press 2 adjacent the ink transfer train 3 and apump member 26 (FIG. 1A) mounted in spaced relation to the spray member25 but connected thereto with multiple hoses, as described below.

The spray member 25 has an elongated body portion 27 (FIG. 3) mounted onthe press 2 longitudinally adjacent the inking rollers 9, 8 and 16. Thebody portion 27 is secured at one end 28 by means of a clamp 29 engagedwith a supporting rod 30 extending across and suitably anchored to theside walls of the printing press 2. The end 28 has a threaded stud 31projecting longitudinally therefrom and threadedly received in a knurledcircular nut 32 which is removably nested within a slot 33 formed in theclamp 29. The manual rotation of the nut 32 urges the body portion 27longitudinally of the stud 31 in either direction, depending upon thedirection of nut rotation.

The other end 34 of the body portion 27 has a plurality oflongitudinally projecting passageway connectors 35 and 36 which arereceived in a mounting block 37 secured to the supporting rod 30 bymeans of a clamp 38 similar to clamp 29 noted above. The block 37 hassockets 38 for receiving the passageway connectors 35 and 36 and guidepins 39 projecting from a back plate 41. The back plate 41 also supportsthe stud 31 and is secured to the rear surface of the body portion 27.The clamps 29 and 38 are spaced apart a distance sufficient to permitunplugging and reconnecting the passageway connectors 35 and 36 andguide pins 39 upon rotation of the nut 32 in opposite directions,whereupon the spray member 25 may be conveniently removed and replacedas desired. The stud 31 is laterally withdrawn, that is, toward the leftas shown in FIG. 1B, from a slot 42 formed in the clamp 29 when removingthe spray member 25.

A plurality of spray nozzles 43 are secured in linear, laterally spacedrelation on the spray member body portion 27 and are directed, in thisexample, toward the nip between the roller 17 and lowermost roller 9,FIG. 1B. The spray nozzles 43 are preferably of the fine spray typemarketed by Spraying Systems Co. of Bellwood, Illinois, designated No.2050. The nozzles 43 have threaded mounting portions received inthreaded bores 44 extending into the body portion 27 and arecharacterized by a central passageway 45 directed axially therethroughand having a fine exit opening 46 (FIG. 7) at the exposed tip. Thepassageways 45 communicate rearwardly into chambers 47 which are fedthrough a passageway 48 drilled transversely into the body portion 27.The passageways 48 connect with elongated slots 49 (FIG. 5) milledlongitudinally into the rear surface 50 of the body portion 27 wherebyupon mounting the back plate 41, for example, by means of suitablescrews 51, the respective slots 49 form individual passageways. Theslots 49 connect with transverse bores 52 which in turn connect withlongitudinal bores 53, the latter receiving the passageway connectors 35thereinto.

The threaded bore 44 is surrounded by a tubular recess 54 whichcommunicates at the outer end thereof with nozzle passageways 55 and atthe inner end thereof with an elongated bore 56 extending into the bodyportion 27 along the bank of nozzles 43.

As discussed further below, the slots and passageways 49, 48 and 45carry dampening liquid in measured quantities to the respective nozzles43 and the bore 56, recess 54 and nozzle passageways 55 carry compressedair for atomizing and propelling the liquid from the nozzle. The block37 (FIG. 3) serves both as a connector-mount for the spray member 25 andan anchor to receive liquid transmitting hoses 57 and a compressed airtransmitting hose 58, the hoses leading from the pump member 26 nowdescribed.

The pump member 26 (FIGS. 1A and 2) comprises a frame 59 mounted, inthis example, by means of a bracket 60 to a convenient location on theframe of the press 2 near the spray member 25. The frame 59 includes amanifold block or portion 61 into which the hoses 57 and 58 communicate.

In this example, an individual valve block 62 is provided for each ofthe nozzles 43. The blocks 62 include a pump recess 63 extendingthereinto from an exterior surface 64, the recess 63 here being formedby bores extending through the block. The blocks 62 are mounted bysuitable screws 65 onto the manifold portion 61 with the recess 63against an exterior surface 66 of the manifold portion 61. A pluralityof bores 67 extend in laterally spaced relation through the manifoldportion 61 and are respectively axially aligned with the recesses 63.Flexible diaphragm seals 68 have a front surface 69 and a rear surface70 and are positioned between the respective recess 63 and the bores 67.The diaphragm seals 68 cover the respective recess 63 with the frontsurface 69 thereof and isolate the respective recesses from the manifoldportion bores 67.

Plungers 71 are reciprocably received in the respective manifold portionbores 67 and bear at a forward, rounded end 72 against the respectivediaphragm seal rear surface 70. Helical compression springs 73 surroundthe respective plungers 71 and bear against a collar 74, urging thediaphragm seal 68 into sealing engagement with the respective blockexterior surface 64. The collar 74 slidably receives the end 72 of therespective plunger 71 therethrough, permitting reciprocal movement ofthe plunger against the diaphragm seal 68 without relieving the sealingpressure that the collar 74 exerts on the diaphragm seal. The other endof the helical spring 73 bears against an integral shoulder 75 formed onthe respective plungers 71. thus urging the plunger resiliently awayfrom the diaphragm seal 68.

The plungers 71 have projections 76 extending outwardly beyond theexterior surface 77 of the manifold portion 61 and received into sockets78 located in the drive ends 79 of respective rocker arms 80. The rockerarms 80 each have an adjusting end 81 opposite from the drive end 79 andcontaining a socket 82 opening laterally in the same direction as thesocket 73. A fulcrum rod 83 is anchored in side plates 84 and 85, whichform part of the pump member frame 59, and extends along the manifoldportion 61. The fulcrum rod 83 engages each of the respective rockerarms 80 at a point opposed to the rocker arms 80 and located between thedrive and adjusting ends, as at 86, FIG. 1.

The sockets 82 receive the tips 87 of adjusting members 88, each havinga handle 89 and a threaded extension 90 received in threaded bores 91extending through the manifold portion 61. The tips 87 bear against therocker arm adjusting ends 81, thereby adjustably limiting the length ofthe reciprocal stroke which can be taken by the respective plungers 71.A suitable spring ball detent 92 is resiliently urged against the handle89 ofthe adjusting members and is selectively received incircumferentially spaced notches 93 for maintaining the adjusting memberin a desired rotary position but permitting easy readjusting by manualrotation ofthe handle.

A drive shaft 94 is rotatably mounted on the pump member 26 in bearingssupported on the mounting plates 84 and 85 and extends along the rockerarms 80. A plurality of eccentric cam rollers 95 are spaced along thedrive shaft 94 and are respectively positioned adjacent the back side 96of the rocker arm drive ends 79. The cam rollers 95 are renderedeccentric with the axis of the drive shaft 94, for example, onethirtysecond inch, through mounting on a bearing 97 having an cecentricinner race or collar, whereby the rotation of the shaft 96 reciprocallydrives the plungers 71 through the rocker arm drive ends 79 although theouter ring 98 of the cam rollers 95 may remain rotationally stationary.A variable speed electric motor 99 is mounted on a support plate 100forming part of the pump member 26 and is operably connected through aright angle gear drive 101 to the shaft 94 for rotating shaft 94 at adesired speed. A suitable universaljoint coupling 102 provides aphysical connection between the motor assembly and the shaft 947Referring to the valve blocks 62, in this example, a flat headed pin 103(FIG. 1A) is contained in the recess 63 bearing against the frontsurface 69 of the diaphragm seal. The body of the pin 103 is receivedaxially within a helical compression spring 104 urging the pin againstthe seal and also bearing against a screw plug 105. The screw plug 105includes a head 106 sealed against the surface 107 of the respectivevalve block 62 by means of a suitable 0" ring 108. Thus, a pump chamber109 is formed by the recess 63 between the screw plug and the diaphragmseal.

Lower and upper drilled passageways 110 and 111 (FIG. 1A) communicateinto the chamber 109 and also respectively into an intake valve chamber112 and an output valve chamber 113 formed in the respective lower andupper portions of the valve blocks 62. The intake valve chamber 112 hasa valve disc 114 resiliently seated therein by means ofa helical spring115 compressed thereagainst with a threaded seal plug 116. The intakevalve chamber 112 communicates through a bore 117 with a manifoldpassageway 118 formed in the manifold portion 61 (FIGS. 1A and 2). Themanifold passageway 118 is branched along its length as at 119, therebycommunicating with each bore 117 in the respective valve blocks 62. Aseal is maintained between the blocks 62 and manifold portion 61 bymeans of suitable 0 rings 120 compressed against the manifold portionsurface 66. The manifold passageway 118 is fed dampening liquid througha mouth 121 connected by suitable fittings 122 to a closed container 123holding the liquid. A suitable plug 124 seals an access port into themanifold passageway 118.

The output valve chambers 113 have valve discs 125 resiliently seatedtherein by means of helical springs 126 bearing thereagainst throughpressure exerted by threaded plugs 127 having central passagewaystherethrough. The passageways in the plugs 127 provide communicationbetween the valve chambers 113 and respective passageways 128 in themanifold portion 61. The passageways 128 receive the ends 129 of thehoses 57, the hose ends being sealed therein through 0" rings 130 urgedinto sealing engagement with pressure exerted by a block 131 secured tothe manifold portion 61 by screws 132.

The output valve chambers 113 have piston rods 133 received partiallythereinto and slidably sealed through 0" rings 134 maintained undercompression with threaded collars 135. Helical compression springs 136surround the piston rod 133 and normally urge same away from the valvedisc 125. A transverse bar 137 bears against each of the piston rods 133moving the bar 137 toward the valve block 62, as by an air cylinder 138,will result in discharging substantially the entire contents of theoutput valve chambers 113.

A motor control 139 (FIG. 1A) ofa known type is adapted to vary theoutput speed of the motor 99. A commercially available sensor 140 isassociated with the drive shaft 24 and is adapted to produce a signalproportional to the rotational speed of the drive shaft and, hence, theweb printing speed of the press. The speed sensor 140 cooperates withthe motor control 139 in a well known manner whereby the rotation of themotor 99 may be directly related to the rotational speed of the driveshaft 24. Preferably, the relationship between the drive shaft speed andmotor speed will not be linearly proportional, since dampeningrequirements have been found to be proportionately higher at lower pressspeeds; however, when the shaft speed is zero, the motor should be offto prevent dripping of unused moisture.

Compressed air, for example at 5 p.s.i.g., is introduced through a hose141 anchored to the manifold portion 61 by a fitting 142. The compressedair is then directed through a fitting 143 (FIG. 2) into the hose 58which feeds the bore 56 through the block 37.

In operation, the dampening liquid, normally comprising a mixture ofwater and certain volatile additives such as isopropyl alcohol, is heldin the container 123 which is closed against external contamination. Thedampening liquid flows downwardly through the fittings 122 into themanifold passageway 118 and branches 119 from which it enters into thebores 117 feeding the intake valve chambers 112. The rotation of themotor 99 at a predetermined speed, in response to the rotation of thedrive shaft 24, causes the drive shaft 94 whereupon to rotate whereuponthe respective bearing outer rings 98 orbit eccentrically. The orbitingof the outer rings 98 periodically'urges the drive ends 79 of the rockerarms 80 toward the respective plungers 71, the length of stroke being,in part, determined by the adjustment of the adjusting members 88. Thatis, the adjusting members 88 adjustably limit the distance the plungersprings 73 may urge the rocker arms 80 toward the rings 98.

The reciprocation of the plungers 71 is reflected in the similarmovement of the diaphragm seals 68, which alternately increase anddecrease the volume of the pump chambers 109, creating positivedisplacement pumping. The return stroke of the diaphragm seals 68 isaided by the springs 104 acting upon the diaphragm contacting pins 103.The volume increase in the chambers 109 causes a reduction in chamberpressure which draws dampening liquid into the bores 117, past the checkvalve discs 114, into the valve chambers 112 and upwardly into thechambers 109 through the passageways 110. The alternate decrease inchamber volume causes the valve discs 114 to close, raising the pressurewithin the chambers 109 and forcing the dampening liquid upwardlythrough the passageways 111 and into the output valve chambers 1 13. Thecontinued sequence of diaphragm seal reciprocation forces the dampeningliquid to open the output valve discs 125 the dampening liquid flowsthrough the passageways 128 and into the respective hoses 57individually feeding liquid in metered quantities to the spray nozzles43. The quantity of liquid supplied to individual nozzles is controlledin relation to the other nozzles by the individual adjusting members 88,while the overall system liquid supply is controlled by the rotationalspeed of the motor 99 as determined by the rotational speed of the driveshaft 24.

Air in the hose 58 is distributed by the body portion bore 56 into therespective tubular recesses 54 (FIG. 7) where it is discharged throughthe respective spray nozzles 43 (FIG. 1B) in a known manner foratomizing and transporting the liquid in minute particles to the inktrain for regulating the ink-water balance required for quality offsetprinting.

Thus, with the use of the above apparatus, there is no contamination orbackfeed of the dampening fluid; the premature evaporation of volatilecomponents is prevented, and precise control is provided over individualportions along the printing plate as well as overall quantityrequirements dictated by press speed.

Due to the very small quantities of liquid being pumped, system primingor bubble clearance may constitute an important consideration inaccurate pump operation. In the abovedescribed apparatus both of thesefunctions are conveniently and effectively accomplished by the periodicactuation of the piston rod 133 by the air cylinder 138 (FIG. 2).Bubbles forming or collecting within the system which could interferewith the pumping function tend to move to the highest point between theintake and output valves, which here constitutes the output valvechamber 113 (FIG. 1A). Depressing the piston rod 133 empties the outputvalve chamber 133 whereby such bubbles which have collected are forceddownstream into the respective hoses 57 where they are harmlesslyeliminated during normal system operation. It has been found sufficienttoprovide an actuating control (not shown) in conjunction with thenormal printing press operating controls (not shown) which causes theair cylinder 138 to be actuated for a single reciprocation each time thepress begins a web printing run.

It is to be understood that although one form of this invention has beenillustrated and described it is not to be limited specifically thereto.

What I claim and desire to secure by Letters Patent is:

l. in combination with a printing press having drive means, an inkingtrain, and an offset plate on a plate cylinder which in turn engages ablanket cylinder for transferring an ink image thereto, dampeningapparatus comprising:

a. a spray member operably directed toward said plate cylinder andhaving a plurality of liquid atomizing spray nozzles positioned on saidpress in laterally spaced relation, said spray nozzles respectivelyhaving unvalved liquid exit openings, gas directing means adjacent saidrespective exit openings for atomizing liquid flow out of said exitopenings, individual dampening liquid output conduit means connected atone end thereof to said respective exit openings,

. a pump member having a plurality of individual metering pumpsrespectively including an input portion containing an input valve, anoutput portion containing an output valve and a pump pathway extendingbetween said valves,

c. said output conduit means being connected at the other end thereof tosaid respective metering pump output portions,

. an output valve chamber in said pump pathway upstream from said outputvalve,

e. reciprocating pump means communicating with said pump pathway betweensaid valves and alternately increasing and decreasing the volume in saidpump pathway,

f. flushing means communicating with said pump pathway and selectivelyoperable in addition to and substantially independently of said pumpmeans to discharge contents of said output valve chamber past saidoutput valve and into said respective output conduit means,

g. a source of dampening liquid including input conduit means connectedto said respective pump input portions,

h. drive means associated with said press drive means for driving saidpump means, and

. means associated with said pump means for individually adjusting thevolume variation in said respective pump pathways,

j. said dampening apparatus being substantially isolated fromatmospheric exposure between said dampening liquid source and said exitopenings.

. The combination as set forth in claim 1 wherein:

said flushing means includes a piston receivable into said output valvechamber.

The combination as set forth in claim 1 wherein: said output valvechamber is elevated above said input valve.

4. The dampening apparatus as set forth in claim 1 wherein:

a. said metering pumps each include a valve block secured to saidmanifold portion,

b. said valve blocks each having said pump pathway therein, and saidreciprocating pump means includes a recess in said respective valveblocks forming a pump chamber.

. The apparatus as set forth in claim 4 wherein:

. said input conduit means includes a manifold portion having aplurality of bores extending therethrough and respectively aligned withsaid block recesses,

b. said reciprocating pump means includes a flexible diaphragm sealhaving front and rear surfaces and positioned between each of saidrespective recesses and manifold portion bores, said diaphragm sealcovering said recesses with said front surfaces and isolating saidrecesses from said manifold portion,

c. a plurality of plungers reciprocally received in said respectivemanifold portion bores and bearing at one end respectively thereofagainst said diaphragm seal rear surfaces,

d. said individually adjusting means includes means for adjustablyreciprocating said plungers against said diaphragm seal rear surface.

6. The combination as set forth in claim 1, wherein:

a. a portion of said inking train is operably positioned between saidspray nozzles and said plate cylinder.

7. The dampening apparatus as set forth in claim 1 wherein:

a. said metering pumps each include a reciprocally mounted plunger fordisplacing said dampening liquid, and

b. a rocker arm operably engaging said plunger, said rocker arm beingadjustably mounted for selectively limiting the stroke length of saidplunger.

8. The dampening apparatus as set forth in claim 1 wherein:

said spray member includes a body portion, and

. said individual dampening liquid conduit means includes elongatedslots extending in said spray member body portion. The dampeningapparatus as set forth in claim 1 wherein:

. said metering pumps each include a reciprocally mounted a drive shaftrotatably mounted on said pump member and extending along said rockerarms, a plurality of eccentric cam rollers spaced along said drive shaftand respectively positioned adjacent said rocker arm drive ends, saidcam rollers being eccentrically offset sufficiently to reciprocablydrive said plungers through said rocker arm drive ends upon rotationofsaid drive shaft,

. a plurality of adjusting members each having a threaded extension,said adjusting member extensions respectively being threadedly receivedin said pump member manifold portion and having ends adjustably bearingagainst said rocker arm adjusting ends for selectively limiting thestroke of said plungers toward said cam rollers, and

. said pump drive means engages said drive shaft for rotating said driveshaft.

lOl029 0130

1. In combination with a printing press having drive means, an inkingtrain, and an offset plate on a plate cylinder which in turn engages ablanket cylinder for transferring an ink image thereto, dampeningapparatus comprising: a. a spray member operably directed toward saidplate cylinder and having a plurality of liquid atomizing spray nozzlespositioned on said press in laterally spaced relation, said spraynozzles respectively having unvalved liquid exit openings, gas directingmeans adjacent said respective exit openings for atomizing liquid flowout of said exit openings, individual dampening liquid output conduitmeans connected at one end thereof to said respective exit openings, b.a pump member having a plurality of individual metering pumpsrespectively including an input portion containing an input valve, anoutput portion containing an output valve and a pump pathway extendingbetween said valves, c. said output conduit means being connected at theother end thereof to said respective metering pump output portions, d.an output valve chamber in said pump pathway upstream from said outputvalve, e. reciprocating pump means communicating with said pump pathwaybetween said valves and alternately increasing and decreasing the volumein said pump pathway, f. flushing means communicating with said pumppathway and selectively operable in addition to and substantiallyindependently of said pump means to discharge contents of said outputvalve chamber past said output valve and into said respective outputconduit means, g. a source of dampening liquid including input conduitmeans connected to said respective pump input portions, h. drive meansassociated with said press drive means for driving said pump means, andi. means associated with said pump means for individually adjusting thevolume variation in said respective pump pathways, j. said dampeningapparatus being substantially isolated from atmospheric exposure betweensaid dampening liquid soUrce and said exit openings.
 2. The combinationas set forth in claim 1 wherein: a. said flushing means includes apiston receivable into said output valve chamber.
 3. The combination asset forth in claim 1 wherein: a. said output valve chamber is elevatedabove said input valve.
 4. The dampening apparatus as set forth in claim1 wherein: a. said metering pumps each include a valve block secured tosaid manifold portion, b. said valve blocks each having said pumppathway therein, and said reciprocating pump means includes a recess insaid respective valve blocks forming a pump chamber.
 5. The apparatus asset forth in claim 4 wherein: a. said input conduit means includes amanifold portion having a plurality of bores extending therethrough andrespectively aligned with said block recesses, b. said reciprocatingpump means includes a flexible diaphragm seal having front and rearsurfaces and positioned between each of said respective recesses andmanifold portion bores, said diaphragm seal covering said recesses withsaid front surfaces and isolating said recesses from said manifoldportion, c. a plurality of plungers reciprocally received in saidrespective manifold portion bores and bearing at one end respectivelythereof against said diaphragm seal rear surfaces, d. said individuallyadjusting means includes means for adjustably reciprocating saidplungers against said diaphragm seal rear surface.
 6. The combination asset forth in claim 1, wherein: a. a portion of said inking train isoperably positioned between said spray nozzles and said plate cylinder.7. The dampening apparatus as set forth in claim 1 wherein: a. saidmetering pumps each include a reciprocally mounted plunger fordisplacing said dampening liquid, and b. a rocker arm operably engagingsaid plunger, said rocker arm being adjustably mounted for selectivelylimiting the stroke length of said plunger.
 8. The dampening apparatusas set forth in claim 1 wherein: a. said spray member includes a bodyportion, and b. said individual dampening liquid conduit means includeselongated slots extending in said spray member body portion.
 9. Thedampening apparatus as set forth in claim 1 wherein: a. said meteringpumps each include a reciprocally mounted plunger for displacing saiddampening liquid, b. a rocker arm for each of said plungers and having adrive end and an adjusting end, a fulcrum rod mounted on said pumpmember and engaging said rocker arms between said drive and adjustingends, said plungers bearing at one end thereof against said respectiverocker arm drive ends, c. a drive shaft rotatably mounted on said pumpmember and extending along said rocker arms, a plurality of eccentriccam rollers spaced along said drive shaft and respectively positionedadjacent said rocker arm drive ends, said cam rollers beingeccentrically offset sufficiently to reciprocably drive said plungersthrough said rocker arm drive ends upon rotation of said drive shaft, d.a plurality of adjusting members each having a threaded extension, saidadjusting member extensions respectively being threadedly received insaid pump member manifold portion and having ends adjustably bearingagainst said rocker arm adjusting ends for selectively limiting thestroke of said plungers toward said cam rollers, and e. said pump drivemeans engages said drive shaft for rotating said drive shaft.